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Sex animals and giles

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Range map of extant Giraffa subspecies. African even-toed ungulate mammals, the tallest living terrestrial sex animals and giles and the largest ruminants.

The giraffe’s chief distinguishing characteristics are its extremely long neck and legs, its horn-like ossicones, and its distinctive coat patterns. It is classified under the family Giraffidae, along with its closest extant relative, the okapi. The giraffe has intrigued various cultures, both ancient and modern, for its peculiar appearance, and has often been featured in paintings, books, and cartoons. Living giraffes were originally classified as one species by Carl Linnaeus in 1758. He gave it the binomial name Cervus camelopardalis. Morten Thrane Brünnich classified the genus Giraffa in 1772.

Cladogram based on a 2003 study by Hassanin and Douzery. The giraffe is one of only two living genera of the family Giraffidae in the order Artiodactyla, the other being the okapi. The family was once much more extensive, with over 10 fossil genera described. The elongation of the neck appears to have started early in the giraffe lineage.

Comparisons between giraffes and their ancient relatives suggest that vertebrae close to the skull lengthened earlier, followed by lengthening of vertebrae further down. The anatomy of Samotherium appears to have shown a transition to a giraffe-like neck. Giraffids like Palaeotragus, Shansitherium and Samotherium appeared 14 mya and lived throughout Africa and Eurasia. These animals had bare ossicones and small cranial sinuses and were longer with broader skulls. Bohlinia entered China and northern India in response to climate change.

From there, the genus Giraffa evolved and, around 7 mya, entered Africa. Further climate changes caused the extinction of the Asian giraffes, while the African giraffes survived and radiated into several new species. In the early 19th century, Jean-Baptiste Lamarck believed the giraffe’s long neck was an “acquired characteristic”, developed as generations of ancestral giraffes strove to reach the leaves of tall trees. The giraffe genome is around 2. 9 billion base pairs in length compared to the 3. 3 billion base pairs of the okapi.

Of the proteins in giraffe and okapi genes, 19. The two species are equally distantly related to cattle, suggesting the giraffe’s unique characteristics are not because of faster evolution. Approximate geographic ranges, fur patterns, and phylogenetic relationships between some giraffe subspecies based on mitochondrial DNA sequences. Colored dots on the map represent sampling localities. The IUCN currently recognises only one species of giraffe with nine subspecies. In 2001, a two-species taxonomy was proposed. Reticulated and Masai giraffes have the highest mtDNA diversity, which is consistent with giraffes originating in eastern Africa.

Populations further north are more closely related to the former, while those to the south are more related to the latter. Giraffes appear to select mates of the same coat type, which are imprinted on them as calves. A 2011 study using detailed analyses of the morphology of giraffes, and application of the phylogenetic species concept, described eight species of living giraffes. A 2016 study also concluded that living giraffes consist of multiple species. The researchers suggested the existence of four species, which have not exchanged genetic information between each other for 1 million to 2 million years. There are an estimated 90,000 individuals of Giraffa in the wild, with 1,144 currently in captivity.

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